Caster.



J. G. LUDWIG.

CASTER.

APPLIGTION FILED MAYM, 1912.

Patented July 23, 1912.

2 SHEETS-SHEET l.

` l WITNESSS dwf J. G. LUDWIG.

GASTER.

API-Lloulon FILED In 14, 1912.

1,033,256. Patented Ju1y23,1912.

2 SHEETS-SHEET 2.

WIT NESSES N orriei.

JOI-Ile] G. LUDWIG, OFJMIDDLEVILLE, NEW YORK.

CASTER.

T (Illa/:hom it may concern.:

Be it known that I, Jer-IN G. Inmvro, a citizen of the United States, residing at Middleville, in the county of I'lerl-:iiner and State of NewV York, have invented a certain new and useful Improvement iu Casters, of

- which the following is afull, clear, and exact description.

The object of this invention is to provide ay ballsbearing casterfspecially applicable to heavy articlesor to articles designed to support heavy loads, of such character as to counteract the tendency of the parts of the bearing .to gape and release vthe bearing balls. The invention, however, is applicable to casters for any use.

The invention consists of a caster having two tiers of ball-bearings arranged one above the other, the caster-attaching plate having a cup for onetier and a race for the other tier of balls, the com ileniental race and cup respectively being ormed in a retaining plate or cap and the caster wheel bracket respectively, Which I will proceed now more particularly to set Iforth and finally cla-i In the accompanying drawings illustrating the invention, in the several figures of which like parts are similarly designated, Figures `1 and 2 are perspective views of a truck and a horse, respectively, commonly used in tanncries and' which are heavyin themselves, and also adapted to support rather heavy loads. Fig. 3 isan elevation-.of one of the casters, showing the ball-bearing in section.

bodying the invention.l 'F ig. 8 is a plan view of the construction shown in Fig. 7.

As illustrated in Figs. to 6 inclusive, spheres are used in the ball-bearings, While in Figs. 7 and 8 rollers are used, and it is' to he understood that by the term ball-bearings I mean to include the use of spheres and rollers as Well. Furthermore, although I have illustrated various forms of ballbearings of the type described, it'is to be understood that I have not thereby attempted to exhaust the variations included Within the scope of the invention.

The truck 1, Fig. 1, is of the table type, andit is supplied with four swiveln'g casters 2; and the horse, Fig. 2, is of ordinarytype and it likewise has four similar casters 2. These two well-known articles are ,here shown merely for'illustrative purposes.

Figs. 4t, 5, 6 and 7vare cross-sec tions of various forms oi': ball-bearings,ein-- specimaan of Letters ement. pnt-@mm1 Jury 23,1915@ Application filed May 14, 1912. Serial No. 697.238. i

Referring to Fig. 3, the caster vvheel l is mounted to turn in a forked bracket. .5, provided with a connecting cross-plate (i, the outer portion of which is made as a ball-cup? to receive the-bearing balls 8. T f pl te 9 for attaching the caster to an article,l has the depending iia'nge 10 inthe ower edge of which is' made the ball-race l1, to copeiate withthe cup 7 to retain the lower tier of balls 8 in place; and said fiange isY made with a ball-cup 12 in its upper edge to receive the balls 13 of the upper tier. The ball-race 14 for the upper tier of balls 13 is made in the flange 15 of a shell-like cup 16, the base 17 of which is arranged parallel with the cross-plate 6 of the Wheel bracket, and has a hub 18 which tits in a hole in tliesaid cro-plate. 19 is an axial bolt or rivet passing through the hub 18 and the 'cross-plate and secured by'fa nut-and vwasher 2O or other means, so that the bracket may turnfreely on the attaching plate 9. l

In the modification shown in Fig. 4, substantiallythe same elements as those just f described are present except that the crossplate 21 is made `shel -like with a depressed socket 22, and the upper bali-race is made in a flat cap 23 having a hub 2-1 to ft and turn in the said socket.

"lhe construction shown in F ig. 5 is substantially like that shown lin Fig.' 4, excepting that thesocket and hub are omitted. That vis tp say, the cross-plate`25 sifiat on top `and the ball-race cap 26 is likewise fiat.

The construction shown'in'Fig. 6 is substantially like that shown in Fig. 3, excepting that the shell-like upper wball-race cap 27 is made without a hub and the cross-plate 28 is without a hole other than one for the passage of the axial bolt or rivet.

In Figs. 7 and 8 is shown an adaptation of a ball-bearing like that shown in Fig. 5, to use rollers 29, here shown as tapering, and in. order to keep these rollers properly spaced apart the cups 30 and 31 may be provided With blocks 32150 alternate with the rollers. i y v j In the useV of ball-bearin casters vWith only one tier of balls, it is ound that unequally distributed stra-ins or shifting .strainsfall upon the airis and tend to-eause i thecup and race'to gape, `and as these partsl are thus worn away the gap widens and thel balls escape. By the several-,constructions f shown, the upper tier of balls takes up these straine. Not only so, butthe "truck nry'h'orse is more easily turned and handled. *ln all 'of these constructions theeap by overlap-` ping the iange serves to connect the attaching; plate and the brackets.

it tvill be noted that the shelllike nieniber i ie indiii'erently a part of the lcap or a part of y ab'bnt which the bracket turns. The bolt or rivet 19 thus is relieved of Sonie strain and its main function confined to fastening the bracket and its attaching plate together.

The casters may be made of anj)7 suitable metal, by casting, dro] iforging, or other procesa suitable to such Work.

(lf course I do not limit my invention to its use upon any particular articles, or to size and proportions of parts. Nor do I limit it to the use of easter Wheels, since substitntesfor Wheels supports may be eni played. l

What I claim is l. A caster, having a bracket and a support therein, Said bracket having a ballcnp and balleA therein, an attaching plate for 5ecuring` the easter to an article, a depending flange on said plate having a. ball-race cooperating with said ball-cup to retain the balls therein and having above said race a ball cup in which is a second tier of balls, a cap having a ball-race eoperat-ing with the cup in the upper part of said flange to retain the balls therein, Said cap also serving to connect the attaching plate and bracket, and means to connect the cap and bracket.

2. A. caster, having an attaching plate provided with a depending flange having al uball race on its lower edge and a ball cup on its upper edge, a caster bracket having a ball cup and balls therein next to the race in the depending flange, balls arranged in the upper cup, a shelldike member arranged between the bracket and the 'attaching plate, and means to connect the bracket and attaching plate so as to retain the balls in their cups.

' In testimony whereof I have hereunto set my hand dthis 10th day of Majf A. D. 1912. JOHN G. LUDWIG.

"Witnesses:

HAROLD G. Bomann, GEO. T. Lewis. 

